What Is DNS? A Beginner's Guide

What is DNS? DNS, the Domain Name System, is the internet's phonebook. It turns a name people can remember — like yourbrand.co.tz — into the numeric address of the server that actually hosts your website or email. Without DNS you'd have to type a string of numbers to reach any site. With it, you type a friendly name and the internet quietly looks up where that name should go. This guide explains how DNS works and the handful of records you'll actually use.

How DNS works

When someone visits your domain, their browser asks DNS a simple question: 'where does this name point?' A chain of servers answers, ending with your domain's records, and the browser connects to the address it gets back. That whole lookup usually takes a fraction of a second. You control the answers your domain gives by editing its DNS records — small instructions that say 'send website traffic here' or 'send email there.'

Two terms are worth knowing early. Nameservers are the servers that hold your domain's records — think of them as the specific phonebook your domain uses. TTL (time to live) is how long other computers are allowed to cache an answer before checking again, which is why changes aren't always instant.

The records you'll actually use

There are many record types, but most people only ever touch four. Here's what each one does:

• A record — points your domain to a server's IPv4 address (this is what puts a website online)
• CNAME — points one name to another name (for example, www → your root domain)
• MX record — routes email to your mail provider so messages reach your inbox
• TXT record — holds verification and email-security values such as SPF and DKIM, which stop others from spoofing your email

A practical example

Say you've built a website and your host gives you an IP address. You add an A record pointing your domain at that IP, and a CNAME so the www version points to the same place. To use professional email, you add the MX records your email provider supplies, plus a TXT record for SPF so your messages aren't marked as spam. That's a complete, working setup — and it's just four records.

Managing DNS with SabyDomain

With SabyDomain you edit all of these records from your dashboard with a simple form — no command line, no jargon. If you prefer to host DNS elsewhere, you can instead point your domain to custom nameservers and manage records there. Either way, changes take a few minutes to propagate, and sometimes longer worldwide depending on the TTL you set.

If you haven't registered a name yet, start there — once it's yours, the DNS editor is one click away in your dashboard. New to choosing extensions? Our comparison of .co.tz, .tz and .com can help.

Why DNS changes aren't always instant

When you edit a record, the new value has to spread to DNS servers around the world — a process called propagation. Computers that already looked up your domain keep their cached answer until the TTL expires, so you might see the change immediately on your phone but a colleague across town still sees the old site for a while. Setting a lower TTL before a planned change makes updates take effect faster, which is handy when you're moving a live website to a new host.

Common DNS mistakes

The most frequent slip-ups are simple: pointing an A record at the wrong IP address, forgetting the www CNAME so only the bare domain works, or missing an MX record so email silently fails. If something isn't working, change one record at a time and wait for propagation before trying the next — guessing and changing everything at once only makes problems harder to trace.